Western Ozone Conference
• Understand the nature, causes and trends of ozone in the western U.S. outside CA
• Identify additional assessment work needed to better characterize ozone
• Identify the policy development needed to address the problem
Overview
• Summarize Conference Information
• Discuss Conclusions
• Discuss Recommendations
Conference Overview
• Regulatory Overview– Federal– Early Action Compacts
• Regional Trends– Regional Monitoring Modeling– Mobile Controls
• Case Studies– NM, CO, WA, OR, ID Modeling– WY, AZ, NM Monitoring
• Special topics– Gas Production– Fire
• Not a uniquely important region in terms of impact
• Several studies in North Pacific region over last 2 decades
Why focus on Asian Emissions, North Pacific and US West Coast?
30
25
20
15
10
5
0An
thro
po
ge
nic
NO
x E
mis
sio
ns
(Tg
/ye
ar)
20001995199019851980
North America
Asia+ 5.0 %/year
Europe
• Asian emissions increased significantly over period of studies - Look for parallel change in ambient levels
70
60
50
40
30
20
O3 (pp
bv)
20001996199219881984
CITE 1C
ITCT 2K2
Lassen VolcanicNational Park
Elevated Data setsSites slope O3 2000 r2
(ppbv/yr) (ppbv)Lassen 0.46 ± 0.39 45.8 ± 2.4 0.36Aircraft 0.51 55.3
60
50
40
30
20
10
O3 (pp
bv)
20001996199219881984
Pt. Arena
TrinidadHead
Cheeka Peak
Point ReyesNational Sea Shore
RedwoodNational Park
Marine Boundary Layer Data Sets sites slope O3 2000 r2
(ppbv/yr) (ppbv) 4 sea-level 0.50 ± 0.36 39.9 ± 3.3 0.44 All 5 0.78 ± 0.28 42.9 ± 2.4 0.68
(Data selected to avoid North American influence)
Conclusion: Along the U.S. west coast, springtime O3 has increased by ≈ 0.5 ppbv/yr, i.e. ≈10 ppbv in 20 years or ≈1-1.5 %/yr
Increasing background ozone during spring on the west coast of North America, Jaffe et al., Geophys. Res. Letters, 30, 2003
Springtime mean O3 levels have increased
Summary: In springtime
Impact of Asian Emissions on the Photochemistry of the North Pacific Troposphere
• Asian emissions have increased by ≈ 5% / year over last 20 years
• O3 levels in Eastern Pacific have increased by ≈ 1-1.5 % / year
• PAN levels in Eastern Pacific have increased by ≈ 3-4 % / year
• Pacific photochemistry has become less efficient sink for O3
Caveat: Based on very few “background” data of short time span. 1985 Pt. Arena data are only early PAN and VOC measurements collected over 10 day period
Decreasing Trend, p<=0.15
Decreasing Trend, p>0.15
Increasing Trend, p<=0.15
Increasing Trend, p>0.15
No Trend
Insufficient Data
Trends in Annual 4th-Highest 8-Hour Ozone Average, 1993-2002
Acadia
Big Bend
Cape Cod
Canyonlands
Chamizal
Chiricahua
Channel Islands
Congaree Swamp
Cowpens
Craters of the Moon
Death Valley
Everglades
Glacier
Great Basin
Grand CanyonGreat Smoky MtnsJoshua Tree
Lassen Volcanic
Mammoth CaveMesa Verde
Mount Rainier
North Cascades
Olympic
Pinnacles
Rocky Mountain
Saguaro
Sequoia
Shenandoah
Theodore Roosevelt
Voyageurs
Yellowstone
Yosemite
Denali
55
42
48
N ational Park Service O zone M onitoring N etw ork2002 4th H ighest Daily M axim um 8-Hour O zone Concentrations
(parts per b illion)
<= 84 ppb
85 - 95 ppb
>= 96 ppb
Voyageurs
OlympicNorth Cascades
Mt. Rainier
Glacier
Theo. Roosevelt
Yellowstone
Rocky Mountain
Hawaii Volcanoes
Denali
Virgin Islands
MammothCave Shenandoah
Acadia
Cape Cod
Congaree Swamp
Cowpens
Great SmokyMountains
Big Bend
Chamizal
Mesa Verde
Everglades
LassenVolcanic
Yosemite
Pinnacles
Joshua Tree
Sequoia
Craters of theMoon
Saguaro
Great BasinCanyon-
lands
Grand Canyon
Chiricahua
DeathValley
ChannelIslands
100
62
93
72
8969
66
82
93
69
83
55
52
74
79103
107
75
8570
52
4427
86
87
77
109
86
62
65
66
93
How do ozone concentrations in national parks compare with nearby urban areas?
Ozone Trends at Rocky Mountain NP and Front Range Cities, 1993 - 2002
0
10
20
30
40
50
60
70
80
90
100
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002
An
nu
al 4
th H
igh
est
Dai
ly M
axim
um
8-h
ou
r O
zon
e, p
pb
Rocky Mountain Rocky Flats (08-059-0006) Arvada (08-059-0002) Denver (08-031-0014)
Boulder (08-013-0011) Colorado Springs (08-041-0013) Ft Collins (08-069-1004)
Rocky Flats
Boulder
Denver
Arvada
Rocky Mt NP
Colorado Springs
Ft Collins
85 ppb
Note: Arvada, Colorado Springs, Denver show a statistically significant increase in 4th highest daily maximum 8-hour ozone (p<0.10)
1993-2002 Mar-Sep Diurnal Ozone PatternsRocky Mountain National Park and Selected Urban Monitoring Sites
0
10
20
30
40
50
60
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Hour of the Day
Ozo
ne
Co
nce
ntr
atio
n, p
pb
Rocky Mountain NP
Arvada (08-059-0002)
Ft. Collins (08-069-1004)
Denver (08-031-0014)
Rocky Flats (08-0006-1004)
Do diurnal patterns of ozone differ from parks to nearby urban areas?
1993-2002 Jan-Dec Diurnal Ozone PatternsAt Grand Canyon NP, Saguaro NP, and Selected Urban Monitoring Sites
0
10
20
30
40
50
60
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Hour of the Day
Ozo
ne
Co
nce
ntr
atio
n, p
pb
Phoenix (04-013-1004)
Las Vegas (32-003-0016)Tucson (04-019-1011)
Saguaro NP
Grand Canyon NP
Expected Ozone Trends – Federal Emissions Reductions
• Heavy Duty Engine & Diesel Sulfur– Issued in 2001– Emissions standards for heavy-duty trucks and buses, plus
fuel sulfur limits– 95% less NOx emissions from category– Effective in model year 2006/07, phase in (09/10)
• NonRoad Engine & Diesel Sulfur – Proposed in 2003, Expected final in April 2004 – Emissions standards for construction, agricultural, and
industrial equipment– 90% less NOx emissions from category– Effective in model year 2008, phase in through 2014
-60
-50
-40
-30
-20
-10
0
AZ CO ID OR UT
State / Base Case
Per
cent
Cha
nge
(%)
2020 B
2020 C
2030 B
2030 C
Expected Ozone Trends – Future NOx Emissions Changes
Expected Ozone Trends – NonRoad Modeling Analyses
• Most portions of the western U.S. are projected to have a reduction of 2-10 ppb in peak 8-hr ozone levels by 2020
• Greater reductions in majority of CA
• Disbenefits in LA, SF, DEN (small) & PHX (small)
Legend
53 - 70
71 - 79
80 - 84
85 - 89
90 - 94
95 - 129
Number of Counties
(97)
(108)
(151)
(71)
(67)
Nonroad (CAMX) 8 hour
(27)
1999-2001 Design Values
1999-2001 Eight Hour Ozone Design Values
Projected 2020 Eight Hour Ozone Design Values
Legend
DV2020B
43 - 70
71 - 79
80 - 84
85 - 89
90 - 94
95 - 133
Number of Counties
(154)
(39)
(16)
(9)
(5)
Nonroad (CAMX) 8 hour
(299)
2020 Base Design Values
50556065707580859095
100
2001-2003
2020 B 2020 C 2030 B 2030 C
Maricopa
Pima
Expected Ozone Trends – NR Modeling: Arizona
Expected Ozone Trends – NR Modeling: Colorado
50556065707580859095
100
2001-2003
2020 B 2020 C 2030 B 2030 C
Jefferson
Larimer
Expected Ozone Trends – NR Modeling: Nevada
50
55
6065
70
75
80
8590
95
100
2001-2003 2020 B 2020 C 2030 B 2030 C
Clark
Expected Ozone Trends – NR Modeling: New Mexico
50556065707580859095
100
2001-2003
2020 B 2020 C 2030 B 2030 C
Bernalillo
Dona Ana
San Juan
Expected Ozone Trends – NR Modeling: Oregon
50556065707580859095
100
2001-2003
2020 B 2020 C 2030 B 2030 C
Clackamas
Columbia
Lane
Marion
Expected Ozone Trends – NR Modeling: Utah
50556065707580859095
100
2001-2003
2020 B 2020 C 2030 B 2030 C
Davis
Salt Lake
Utah
Weber
Expected Ozone Trends – NR Modeling: Washington
50556065707580859095
100
2001-2003
2020 B 2020 C 2030 B 2030 C
Clark
King
Pierce
Thurston
Expected Ozone Trends – NonRoad Modeling Analyses
• 8-hour ozone levels are generally expected to decrease slightly in the Western U.S. over the next 10-25 years– Decrease of ~ 5%: Albuquerque, Denver, Phoenix,
Salt Lake City, Tucson, & rural areas– Larger decreases: Portland, Seattle – Model results uncertain (your results may vary)– Certain Western U.S. cities are likely to maintain
design values near/just below the NAAQS over the next 0-20 years w/o local control
• – will depend on year-to-year meteorological variability.
CMAQ Western U.S. Ozone Modeling – 1996 Application
• Model performance evaluation indicated greater negative bias in the western U.S. in the summer than in 36/12 CAMx
– Mean normalized bias = -11.7%– Normalized gross error = 23.2 %– East US (annual): bias = -1.2%; error
= 18.6%– West US (annual): bias = -26.5%;
error = 29.9%– East US (summer): bias = 0.8%;
error = 18.7%– West US (summer): bias = -27.0%;
error = 30.5%
2007 Emission Reduction Sensitivity Analysis
• Across-the-Board 10% reduction in anthropogenic emissions in DMA + Weld County (plus on-road and off-road reductions).
• Key Findings:– Modeled ozone stiff response to local emission
reductions (i.e., ozone not very responsive to local emission controls)
– VOC control in DMA is more effective than NOx control in DMA
• 10% VOC control in DMA results in 0.3-0.4 ppb ozone reduction at Rocky Flats North monitor
• 10% NOx control in DMA results in 0.4 ppb ozone increase at Rocky Flats North monitor
Denver Ozone Source Apportionment
• Source Apportionment results currently under review by State and Denver RAQC, report not yet available
• Preliminary results suggest the following:– A majority (~75% to 85%) of the peak 8-hour ozone
concentrations at the Rocky Flats monitor come from outside of the Denver Metropolitan Area (DMA)
– For sources in the DMA, on-road mobile sources are most important followed by non-road mobile sources
• Helps explain why modeling results are so stiff in response to local controls
1-Hr Ozone Model Performance, Error – Goal < 35%Mean Normalized Gross Error in 1- Hr Ozone, (%).
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
40.0
04-Jun
05-Jun
06-Jun
07-Jun
08-Jun
Average
Gro
ss E
rror
, %
4 Km Domain12 Km Domain36 km DomainSan Juan Basin
Overall Conclusions Western US O3 Modeling
• Ozone downwind of smaller “urban” areas in western U.S. tends to be underestimated– Seen in recent EACs (CAMx) and Regional Visibility
modeling (CMAQ)– Regional buildup of ozone understated
• Contributing factors:– Missing emissions
• UCI Oil&Gas, many small unpermitted sources• Missing biogenic emissions/understated reactivity• Mobile Source fleet type different from national average
– Meteorological Modeling More Challenging
2002 Denver Metro and Statewide
VOC EI with Biogenic Emissions
Point Sources7 %
Point Sources-F lash15 %
Area Sources11 %
N on-R oad (exhaust)7 %
N on-R oad (evaporative)1 %
M obile Sources (exhaust)9 %
M obile Sources (evaporative)8 %
B iogenic43 %
D e n ve r EAC -2 0 0 2 H yd ro ca rb o n Em issio n s fo r th e D e n ve r A re a + W e ld C o u n ty w ith B iog e n ic Em issio n s
(To ta l H C =8 9 3 tp d )
Point Sources2 %
Point Sources-F lash2 %
Area Sources3 %
N on-R oad (exhaust)2 %N on-R oad (evaporative)0 %
M obile Sources (exhaust)2 %
M obile Sources (evaporative)2 %
B iogenic88 %
D e n ve r EAC -2 0 0 2 S ta te w id e H yd ro ca rb o n Em issio n s+ B io g e n ic Em issio n s a n d W ild fire
(To ta l H C = 7 3 7 8 tp d )
MT Emission InventoryCoal Bed Methane Sources
MT Emission InventoryConventional Oil & Gas Sources
July 19, 2002
10:15 am
SVR = 130 km
O3 = 78 ppb
11:45 am
SVR = 54 km
O3 = 86 ppb
July 19, 2002 (3:00-3:45 pm)
SVR = 58 km O3 = 96 ppb (highest O3 value in 2002)
Maximum Daily 1- Hour Ozone Measurements, July - August, 2000
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
7/1/
2000
7/3/
2000
7/5/
2000
7/7/
2000
7/9/
2000
7/11
/200
0
7/13
/200
0
7/15
/200
0
7/17
/200
0
7/19
/200
0
7/21
/200
0
7/23
/200
0
7/25
/200
0
7/27
/200
0
7/29
/200
0
7/31
/200
0
8/2/
2000
8/4/
2000
8/6/
2000
8/8/
2000
8/10
/200
0
8/12
/200
0
8/14
/200
0
8/16
/200
0
8/18
/200
0
8/20
/200
0
8/22
/200
0
8/24
/200
0
8/26
/200
0
8/28
/200
0
8/30
/200
0
pp
m o
zon
e
Beach
Bountiful
Cottonwood
Herriman
Highland
Hawthorne
Logan
North Ogden
North Provo
Spanish Fork
Washington Terrace
West Valley
O3 1 Hr Max. Entire Wasatch Front - Aug '02
28-A
ug
10-A
ug
3-A
ug
19-A
ug
0
0.02
0.04
0.06
0.08
0.1
0.12
1-Aug
2-Aug
3-Aug
4-Aug
5-Aug
6-Aug
7-Aug
8-Aug
9-Aug
10-A
ug
11-A
ug
12-A
ug
13-A
ug
14-A
ug
15-A
ug
16-A
ug
17-A
ug
18-A
ug
19-A
ug
20-A
ug
21-A
ug
22-A
ug
23-A
ug
24-A
ug
25-A
ug
26-A
ug
27-A
ug
28-A
ug
29-A
ug
30-A
ug
31-A
ug
Day of the Month
O3
pp
m
Brigham City Logan Bountiful Salt Lake Beach Hawthorn West Vall Harriman
West Prov Highland Spanish F Washingto North Ogd
Conclusions
• Future not clear/national view may need refinement • Many examples, but lack of regional understanding of:
– Background, natural, rural/urban, transport/local, regional, subregional-Elevated urban ozone not well synchronized with rural ozone
• Better analysis of existing situation needed• ID policy goals – attainment, maintenance,
transport/local, rural/urban, regional/subregional• Coordinate/leverage resources• High background levels – limited local control options
Recommendations
• Modeling– Biogenics, meteorology– One atmosphere model
• Monitoring – Work with existing data – Better collaboration– Better spatial coverage– Collect speciated VOC and NO
Recommendations (cont.)
• Early Action Compacts– Encourages proactive assessment/action-to identify/address
problems before they become nonattainment areas– Continue to make option available
• Forecasting – continue federal support• IAQR – understand effect on ozone• Oil and gas – getting better understanding of emissions• Fire/ozone
– Resolve fire/ozone episode relationship/documentation – Resolve monitor interference question
Questions?
?